US3929474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tarnish resistant silver based dental casting alloy capable of bonding to porcelain
Assignee: Williams Gold Refining Co Inc
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Filing: 1974-08-05
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Granted: 1975-12-30
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Expires: 1994-08-05
Abstract
Abstract An alloy composition comprising about 35-60% Pd, at least about 0.5-7% of one member of the group consisting of Cr, Fe, In and Sn and from about 0 to 5% of the group consisting of Si, Ni, Co, Ta, and Ti, and the rest Ag, has been found useful in the dental arts where a porcelain is required to be fused directly to the alloy.
Inventors
- 👤 Clyde E Ingersoll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:27
CPC Classifications
C; C22; C22C; C22C5/00; C22C5/04; A; A61; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/844; C22C5/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
115 words
AN ALLOY CONSISTING ESSENTIALLY OF ABOUT 28-64% AG, ABOUT 37.5-57.7% PD, ABOUT 0.5-7% OF AT LEAST ONE MEMBER OF THE CLASS CONSISTING OF CR, FE. IN AN SN AND FROM 0 TO ABOUT 5% OF A MEMBER OF THE CLASS CONSISTING OF SI, NI, CO, TA, TI, ALL TOTALLING 100%; SAID ALLOY HAVING A VICKERS HARDNESS OF 150-220; SAID ALLOY WHEN CONTAINING SN FURTHER CONTAINING A MEMBER SELECTED FROM THE GROUP CONSISTING OF ABOUT 0.5% IN, 1.0% TI, 5.0% NI, 17% SI, AND 5% FE; AND SAID ALLOY WHEN CONTAINING FE FURTHER CONTAINING A MEMBER SELECTED FROM THE GROUP CONSISTING OF ABOUT 0.5% TA, ABOUT 2.0% NI, AND ABOUT 0.5% IN AND ABOUT 0.5% SN.
Claim 2
Dependent Claim
115 words
AN ALLOY CONSISTING ESSENTIALLY OF ABOUT 28-64% AG, ABOUT 37.5-57.7% PD, ABOUT 0.5-7% OF AT LEAST ONE MEMBER OF THE CLASS CONSISTING OF CR, FE. IN AN SN AND FROM 0 TO ABOUT 5% OF A MEMBER OF THE CLASS CONSISTING OF SI, NI, CO, TA, TI, ALL TOTALLING 100%; SAID ALLOY HAVING A VICKERS HARDNESS OF 150-220; SAID ALLOY WHEN CONTAINING SN FURTHER CONTAINING A MEMBER SELECTED FROM THE GROUP CONSISTING OF ABOUT 0.5% IN, 1.0% TI, 5.0% NI, 17% SI, AND 5% FE; AND SAID ALLOY WHEN CONTAINING FE FURTHER CONTAINING A MEMBER SELECTED FROM THE GROUP CONSISTING OF ABOUT 0.5% TA, ABOUT 2.0% NI, AND ABOUT 0.5% IN AND ABOUT 0.5% SN.
Claim 3
Dependent Claim
25 words
The alloy of claim 1 wherein the composition is about 37.5% Pd, about 0.5% In, about 0.5% Sn, about 1% Ti and the balance Ag.
Claim 4
Dependent Claim
24 words
The alloy of claim 1 consisting essentially of about 48% Pd, about 5% Fe, about 0.5% In, about 0.5% Sn, and the balance Ag.
Claim 5
Dependent Claim
21 words
The alloy of claim 1 consisting essentially of about 46.5% Pd, about 2% Fe, about 2% Ni and the balance Ag.
Claim 6
Dependent Claim
21 words
The alloy of claim 1 consisting essentially of about 45.9% Pd, about 4% Fe, about 0.5% Ta and the balance Ag.
Claim 7
Dependent Claim
21 words
The alloy of claim 1 consisting essentially of about 45% Pd, about 2% Cr, about 2% Co and the balance Ag.
Claim 8
Dependent Claim
24 words
The alloy of claim 1 consisting essentially of about 57.7% Pd, about 1% In, about 1% Sn, about 5% Ni, and the balance Ag.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |